What happens if 'throw' fails to allocate memory for exception object?

Question

From C++11 standard (15.1.p4):

The memory for the exception object is allocated in an unspecified way, except as noted in 3.7.4.1

Answer 1

[intro.compliance]/2 Although this International Standard states only requirements on C++ implementations, those requirements are often easier to understand if they are phrased as requirements on programs, parts of programs, or execution of programs. Such requirements have the following meaning:

(2.1) — If a program contains no violations of the rules in this International Standard, a conforming implementation shall, within its resource limits, accept and correctly execute that program.

Emphasis mine. Basically, the standard envisions failure to allocate dynamic memory (and prescribes behavior in this case), but not any other kind of memory; and doesn't prescribe in any way what the implementation should do when its resource limits are reached.

Another example is running out of stack due to a too-deep recursion. Nowhere does the standard say how deep a recursion is allowed. The resulting stack overflow is the implementation exercising its "within resource limits" right-to-fail.